Turbochargers are used in engines to provide boost for increased engine power output or for enabling a downsized engine to produce an equivalent amount of power as a larger naturally aspirated engine. However, it may be desirable to adjust the amount of boost provided to the engine during certain operating conditions. Therefore, turbocharger wastegates positioned in turbine bypasses have been developed to enable boost adjustment in the engine.
U.S. Pat. No. 7,823,825 discloses a mechanical linkage coupling a solenoid to a wastegate. The mechanical linkage is provided with a flexible rod enabling a greater range in opening pressures of the wastegate to simplify wastegate set-up and calibration.
However, the inventors have recognized several drawbacks with the wastegate disclosed in U.S. Pat. No. 7,823,825. Due to the high speed of the exhaust gases and the turbulent flow patterns around the wastegate valve, the wastegate valve may experience unwanted audible vibrations, referred to as wastegate chatter. The noises may be unpleasant to the vehicle operator and the vibration may decrease the longevity of the wastegate. As a result, customer satisfaction and turbocharger reliability are decreased.
The inventors herein have recognized the above issues and developed a turbocharger wastegate that includes a cover plate actuatable in an open and closed position, the open position enabling exhaust gas flow through a turbine bypass conduit and the closed position inhibiting exhaust gas flow through the turbine bypass conduit. A vibration-dampening extension is coupled to the cover plate radially extending beyond a radial periphery of the cover plate.
It has been unexpectedly found that a side-force imparted on the cover plate via the vibration-dampening extension reduces vibration of the wastegate during operation. As a result, customer satisfaction and turbocharger longevity are increased.
The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure. Additionally, the above issues have been recognized by the inventors herein, and are not admitted to be known.